On the day of the purchase, I was disappointed, turned on my favorite track "Kartel - simfony", a mixture of instruments and electronics, Hardcore in general, at full volume (Iphone 4) in some fragments of the melody it cut my ears with sound . look at the search engine).
Warmed up like better (per day).
I bought the EQu app (Ios player with advanced equalizer, the first app I bought in a couple of years) well, good sound comes at a cost.
I set up the equalizer, the sound became even better, See full review